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arXiv:1303.6202 · Physical Review A

Shaping frequency-entangled qudits

Christof Bernhard, Bänz Bessire, Thomas Feurer, André Stefanov

Published Sep 23, 2013• 104 citations
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Abstract

We demonstrate the creation, characterization, and manipulation of frequency-entangled qudits by shaping the energy spectrum of entangled photons. The generation of maximally entangled qudit states is verified up to dimension $d=4$ through tomographic quantum-state reconstruction. Subsequently, we measure Bell parameters for qubits and qutrits as a function of their degree of entanglement. In agreement with theoretical predictions, we observe that for qutrits the Bell parameter is less sensitive to a varying degree of entanglement than for qubits. For frequency-entangled photons, the dimensionality of a qudit is ultimately limited by the bandwidth of the pump laser and can be on the order of a few millions.

DOI
10.1103/physreva.88.032322

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